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Even Quarks Decay |
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In scientific progress, old ideas are seldom completely replaced, but their range of applicability is seen to be restricted. Such was the case with the idea of neutron decay. A neutron can decay into a proton, electron, and neutrino. But when physicists determined that the neutron is composed of quarks, one up quark and two down quarks, they realized that the neutron itself was not decaying, but rather one of the quarks. Thus quarks shed light on the actual workings of particle interactions that had previously seemed impossible to explain. |
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| Neutron beta decay is when a neutron (udd) decays into a proton (uud), an electron, and an antineutrino. | The neutron is a chargeless particle composed of one up quark and two down quarks. | When the decay occurs, one of the down quarks transforms into an up quark. Since the down quark has a charge of -1/3 and the up quark has a charge of 2/3, charge must be conserved. This is done through the release of a virtual W-, a particle with a charge of -1. |
The neutron has now become a proton. As the virtual W-particle rebounds away from the proton, it transforms into an electron and antineutrino. |
Finally, the proton, electron, and antineutrino all move away from one another. In reality, this entire process only takes a billionth of a billionth of a second. |